Bodies made of wood or wood-like materials can, for example, be connected through mechanical connection means, such as, for example, screws or nails, or through gluing, in which, in the last case, an adhesive is usually applied on both of the connection surfaces to be connected and both of the connection surfaces are then pressed together during a drying or hardening time which is dependent on the type of the adhesive. In a similar manner, bodies made of wood or wood-like materials can also be connected with synthetic material bodies.
These connection methods are disadvantageous for certain uses, since they could, for example, damage applied varnish or colour layers or they could discolour them and/or need a relatively long drying or hardening time.
In WO 96/01377 an alternative method for connecting such bodies is disclosed, in which between the connection surfaces of the bodies to be connected a thermoplastic layer is arranged as connection means. The connection surfaces and the interlying connection means are then held together and at least one of the bodies is mechanically stimulated, in order to produce friction and thus frictional heat, which causes the melting of the thermoplastic layer. Afterwards the mechanical stimulation is stopped and the melted thermoplastic, which is sticking on both connection surfaces, is cooled through drawing off heat in the surrounding body parts, whereby it changes its aggregation condition and becomes hard again.
Disadvantageous with this connection is that the connection means is thermoplastic and therefore has only a limited heat resistance. Many thermoplastics have also a poor resistance against climatic factors, such as, for example, moisture and/or UV radiation. In addition, the dissociation energy of the connection is relatively low, since during the connection no chemical reaction takes place. Finally, the quantity of heat needed for the melting process has to be removed out of the region of the weld spot through drawing off heat, so that hardening of the melted thermoplastic is possible. During this process the connection surfaces have to be held together, i.e. a rest period is necessary after stopping the mechanical stimulation, which is dependent on the properties of the thermoplastic, which can not be easily influenced by the user.
GB 1 311 177 A discloses a method for connecting a container with a cover by means of ultrasonic welding, wherein the connection means can be a cross-linkable resin. The ultrasonic welding is made however with a very high frequency of 20 kHz to 100 kHz, which has consequences for the movement of the connection surfaces to be connected.
In view of the disadvantages of the previously known, above described connection methods, the object of the invention is to provide a method for connecting two bodies of the type mentioned in the introductory part, with which a composite is producible which is more heat-resistant than a comparable composite produced with the method proposed in WO 96/01377. Preferably, in addition the connection method should be able to be better optimised by the user and the connection be able to be produced faster.